Dynamic patella brace and method

ABSTRACT

A dynamic patella brace having a first knee enveloping member with an aperture adapted to expose the patella, and a device for applying medial pressure to the patella. A mounting system for substantially freely floatingly mounting the device for applying medial pressure on the knee enveloping member laterally of the aperture so that the device for applying medial pressure moves relative to the knee enveloping member in vertical and horizontal directions and automatically tracks vertical movements of said patella throughout the physiological range of flexion and extension of the knee while applying medial pressure to the patella, the mounting accommodating horizontal excursions; thereby allowing more controlled horizontal medial pressure and tracking vertical movements of the patella. Preferably, the device for applying medial pressure includes a patella pad, and the knee enveloping member is an elastomeric sleeve. The device for floatingly mounting the patella pad on the elastomeric sleeve includes a patella bracing strap and an anchor point on the sleeve spaced outwardly from the aperture.

This is a continuation-in-part of my application Ser. No. 08/378,606filed Jan. 26, 1995 entitled DYNAMIC PATELLA BRACE WITH FLOATING PATELLAPAD, now U.S. Pat. No. 5,613,943.

FIELD OF THE INVENTION

The present invention relates to knee support and treatment devices, andmore particularly to a dynamic patella brace for stabilizing the patellato prevent patella subluxation, chondromalacia and other symptomaticconditions of the extensor mechanism during all normal degrees of kneeflexion and extension, utilizing a patella force device which applies amedial force on the patella which force dynamically more faithfullytracks vertical and horizontal movement of the patella.

BACKGROUND OF THE INVENTION

It is well known that loosely ligamented individuals, as well asindividuals with certain peculiar anatomic features of certaincomponents of the knee, frequently develop various pathological problemswith their knees, particularly when these individuals are active inphysically strenuous activities, such as, for example, athletics. Themost commonly occurring problems relate to stretching or tearing ofvarious knee ligaments, injury to the cartilage (meniscal) and articularsurfaces of the knee joint, and fractures. Patella subluxation, orabnormal and undesirable movement of the patella, laterally, relative toits normal up-and-down movement in the vertical track defined by thetrochlea, can precipitate the onset of chondromalacia or aggravateexisting chondromalacia of the patella, as well as cause diagnosticproblems and other painful clinical conditions with respect to the knee.

Subluxation of the patella can be caused by certain developmentalabnormalities of the skeletal components of the knee and/or the presenceof musculoligamentous laxity, trauma or dysplasia. The patella may leaveits normal vertical tracking groove as a result of abnormal vectorforces and/or by passive lateral or rotary forces. The abrupt abnormallateral displacement of the patella from its groove during anyweight-bearing activity, such as, for example, running, stair climbing,etc., frequently results in an immediate, temporary disability, such as,for example, buckling of the knee, thereby causing a subjectivesensation in the knee similar to that caused by other unrelatedpathological conditions within the knee. The sensation of pain and/orimminent buckling of the knee results in apprehension and restriction ofcertain weight-bearing activities, such as, for example, athleticendeavors. The resultant increased abnormal traction forces on theperipatellar soft tissues frequently lead to inflammatory changes andstretching of the retinaculae, patella ligament, patellor tibial and/ortendon (tendinitis-strain).

Furthermore, the repetitive, abnormal lateral excursions, which causeabnormal shearing forces, frequently lead to early, accelerated andprogressive degenerative changes (chondromalacia) of the patella andfemoral condyles.

As noted above, problems peculiar to the patella comprise only a portionof all common physiological problems of the knee, and several, unrelatedor partially related problems may occur simultaneously, particularly inindividuals having loose ligaments, or when engaged in relativelystrenuous activities involving the knee.

Young children still in the active bone-growth phase of life frequentlyare relatively loosely ligamented and suffer from various degrees ofpatella subluxation. It is well recognized that it is preferable toavoid or delay corrective surgery for such individuals, if at allpossible, until such individuals reach a more physiologically opportuneage, i.e., when their growth plates have closed.

A discussion of prior brace patents can be found in my patentapplication Ser. No. 08/378,606 filed Jan. 26, 1995, now U.S. Pat. No.5,613,943.

From time to time herein where the term "pad" is used, it is intended toencompass any device which applies or transfers external medial forcesto the patella or knee cap. It can be of single or multilayered fabricwhich is freely floating relative to the knee mounting structure such asan enveloping knee sleeve and knee wrap devices. The basic objective isthat application of medial force track vertical and horizontal movementof the patella as closely as possible substantially throughout the fullrange of knee movement. The term "knee enveloping member"includesflexible endless sleeves, flexible straps and equivalent flexiblemembers.

SUMMARY OF THE INVENTION

The present invention provides an improved dynamic patella brace thatovercomes deficiencies of known patella bracing systems and is animprovement over my prior invention described in U.S. Pat. No.4,296,744. In particular, the present invention provides a dynamicpatella brace wherein a medial patella force means may more effectivetrack vertical and/or horizontal movement of the patella so as tomaintain its most effective operative position with respect to thepatella when the knee is flexed.

It is an object of the invention to provide an improved dynamic patellabrace wherein the medial patella force means or device dynamicallyfloats when the knee is flexed and which more effectively controls thehorizontal pressure applied to the patella.

Another object of the invention is to provide an improved dynamicpatella brace that maintains the medial patella force means in the mosteffective position with respect to the patella during flexion of theknee.

Another object of the present invention is to provide an improveddynamic patella brace having a patella force means adapted to bettercontrol of medial and/or horizontal tension.

Still another object of the present invention is to provide an improveddynamic patella brace useful for both diagnosis and treatment of patellainstabilities.

A further object of the present invention is to provide an improveddynamic patella brace for alleviating certain physiological problems ofthe knee related to, or aggravated by, patella subluxation.

Yet another object of the present invention is to provide an improveddynamic patella brace capable of performing its bracing or splintingfunction for the patella during the full, or normal, range of kneeflexion and movement.

A still further object of the invention is to provide an improveddynamic patella brace to facilitate proper and positive diagnosis ofpatella subluxation, particularly in its milder form when its clinicalpresentation simulates that of other pathological conditions of theknee.

Another object of the present invention is to provide an improveddynamic patella brace suitable for use in children having patellasubluxation, but whose growth plates are still open, so as to delay oravoid the need for corrective surgery until a more physiologicallyopportune time is reached.

A still further object is to provide an improved dynamic patella braceoffering other treatment advantages and for treating painful conditionsof the extensor mechanism.

A further object of the invention is to provide an improved patellabrace which is relatively simple to put in place and which will providedynamic patella bracing without the need for constant adjustment orreadjustment.

Yet another object of the invention is to provide an improved dynamicpatella brace which can be utilized with minimal discomfort withoutbeing unsightly and without requiring the user to utilize crutches or towalk in an unnatural manner.

Another object of the invention is to provide an improved dynamicpatella brace having a relatively simple construction, which isrelatively easy to manufacture.

These and other objects, and their attendant advantages, are achieved bythe present invention, which provides an improved dynamic patella bracecomprising: a knee enveloping member including an anchor, a medial forcemeans mounted on the anchor for applying a dynamic resultant force inthe medial direction to the patella throughout substantially thecomplete physiologic range of flexion and movement of the knee when thebrace is in use; the anchor member, arranged to be disposed laterallyadjacent the medial force applying means so as to maintain the medialforce means positioned laterally adjacent to the patella throughout thecomplete functional physiologic range of motion and movement of the kneeand more closely track vertical movements of the patella. Anintermediate elastic member is adapted to be disposed between the anchorand the medial force means to allow the patella bracing pad to floatwith the movement of the knee and to be dynamically repositionedvertically and horizontally depending upon the amount of flexion andmovement of the knee when the brace is in use. The knee envelopingmember is preferably an elastomeric sleeve having an aperture forreceiving the patella of the user and adapted to have the kneepositioned substantially therein enables the anchor to be fastenedthereto in a predetermined location when the brace is in use.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described in detail herein with reference to thefollowing drawings in which like reference numerals refer to likeelements throughout the several views, and wherein:

FIG. 1 is a perspective view of the dynamic patella brace according toone embodiment of the present invention;

FIG. 2 is a rear view of the strap assembly used to position the patellabracing pad and provide a resultant force to the patella when the braceis in use;

FIG. 3 is a perspective view of the elastomeric sleeve of the dynamicpatella brace prior to the attachment of the strap assembly thereto;

FIG. 4 is a perspective view of an alternate embodiment of the patellabrace according to the present invention;

FIG. 5 is a rear view of the strap assembly used to position the patellabracing pad and provide a resultant force to the patella when the braceis in use for the alternate embodiment of the present invention shown inFIG. 4.; and

FIG. 6 is a perspective view of a further embodiment wherein the patella"pad" is a single layer of material.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 shows a perspective view of an embodiment of the dynamic patellabrace according to the present invention. As shown in FIG. 1, thedynamic patella brace 10 includes a knee enveloping member, such as anelastomeric sleeve 20, and strap assembly 30. Sleeve 20 includes anaperture 21 in which the knee is positioned after the sleeve 20 is drawnup on a user's leg. Strap assembly 30 comprises a central strap portion31 elastic arm members 17, 18 and 19 extending therefrom, medial forceapplying means, such as patella bracing pad 15 and anchor pad 15 ispositioned in the inside of the strap assembly, i.e., on the surfaceadapted to engage the outer surface of sleeve 20. The sleeve 20 ispreferably made of an elastomeric material, such as, for example,neoprene rubber. Aperture 21 in sleeve 20 allows for alignment andregistration of the patella in the brace when it is positioned therein.The sleeve 20 is also provided with a fastener 12 for anchoring thestrap assembly 30 to the sleeve 20 during use. The fastener 12 (shown inFIG. 3) is operatively connected to the anchor 16 of the strap assembly30 when the brace is in use. The function of the anchor 16 and fastener12 will be described in more detail below.

The dynamic patella brace 10, according to the present invention, ispositioned on the knee between the upper portion and lower portion ofthe leg of the user (not shown). The elastic arm members 17, 18 of thedynamic patella brace 10 are adapted to be wound circumferentially in afirst direction around the knee of the user when the brace is in use.Each of the elastic arm members 17, 18 is attached to the central strapportion 31 on which is disposed the patella bracing pad 10 and arrangedso that, when circumferentially wrapped in the first direction about theuser's knee when the brace is in use, the bracing pad 15 will cause aresultant force to be applied medially to the user's patella. As shownin FIG. 6, the bracing pad 15'is a single layer of material.

Arm members 17 and 18 include thereon fastening and holding means 22 and23, respectively, which preferably comprise hook-and-loop fastenermeans, or Velcro® strips attached to the elastic arm members 17, 18along the outer band surfaces thereof at positions near the points atwhich the arm members 17, 18 are attached to the patella bracing pad 15.Cooperating fastening and holding means 25, 26 associated respectivelywith the elastic arm members 17, 18 are attached to the inner bandsurfaces thereof, respectively, near the ends thereof furthest removedfrom the point of attachment to the patella bracing pad 15. The patellabrace 10 also includes a dynamic elastic counterarm 19, having one endthereof also attached to the central strap portion 31 which supports thepatella bracing pad 15. The other end of counterarm 19 is adapted to bewrapped circumferentially in a direction opposite to the direction ofthe first and second elastic arm members 17, 18. A fastening and holdingmeans 27, preferably also a Velcro® strip, is attached to the inner bandsurface of the elastic arm member 19, as shown in FIG. 2. When the firstand second elastic arm members 17, 18 are circumferentially wrappedabout the user's knee, they are fastened and held in that position. Thefastening means 25 engages with the fastening means 22 on the arm member17, and the fastening means 26 engages the fastening means 23 on the armmember 18 to hold the arm member 17, 18 in the wrapped position. It isnoted that when the right knee of the user is braced, the first armmember 17 is wrapped circumferentially about the knee above the patella,and the second arm member 18 is wrapped circumferentially about the kneebelow the patella. The opposite arrangement occurs when using the braceon the left knee. These arrangements cause each of the arm members 17,18 to exert pressure in the medial direction, i.e., toward thecenter-line of the user, on the patella bracing pad 15 to cause thepatella bracing pad 15, positioned laterally of the patella, to therebyapply medial or inwardly directed pressure to the patella, therebypreventing patella stabilities when the knee is flexed.

When the counterarm member 19 is circumferentially wrapped around theleg of the user with the end thereof furthest from the patella bracingpad 15, fastened and held by cooperation between the fastening means 27and the fastening means 29, as previously described, it is noted that itwould be possible to fasten the end of the counterarm member 19,circumferentially wrapped about the knee by cooperation between thefastening means 27 and the fastening means 23, 26 associated with thelower arm member 18, instead of the fastening means 22, 25, associatedwith the upper arm member. In either case, the counterarm. member 19serves to dynamically stabilize the position of the patella bracing padon the knee. In addition, counterarm member 19 includes an elasticportion 14, preferably having substantially greater elasticity thancounterarm member 19, disposed adjacent to the anchor 16. The elasticportion 14 is located at a position between the patella bracing pad 15and the anchor 16. The anchor 16 is adapted to be fastened to thefastener 12, which is positioned on the sleeve 20 as described above. Byfixing the anchor 16 to the fastener 12, the two elastic portions 14, 31of the strap member 30 are allowed to operate in differing manners.

In a preferred embodiment, elastic member 14 is made of a material thatis more elastic than that of the strap portion 31 and of the counterarm,member 19. By constructing the strap assembly 30 in this manner, thepatella bracing pad 15 is permitted to float with the movement of theknee to provide more efficient and stable support to the patella duringthe entire range of flexion and movement of the knee when the brace isin use, as will be described herein.

In the dynamic patella brace disclosed in my U.S. Pat. No. 4,296,744,the disclosure of which is incorporated herein by reference in itsentirety, the patella bracing pad resists adjustment of its position andtends to maintain a more fixed position, regardless of the amount offlexion and movement in the knee when the brace is in use. This resultsin the patella bracing pad being maintained in a position of loweredeffectiveness when the knee of the user is flexed. This is believed tobe caused by rigidity of the arm/counterarm assembly when the brace wasin use. The brace of U.S. Pat. No. 4,296,744 held the bracing pad in amore fixed position once the elastic arms were engaged, regardless ofthe stresses placed on the brace as a result of knee flexion by theuser. It has been found that this more rigid maintenance of position maycause less efficient stabilization and lowered effectiveness of thebrace. To overcome this disadvantage, the subject invention permits theposition of the patella bracing pad to be automatically dynamicallyrepositioned based on the amount of flexion and movement of the knee andallows the user to adjust the pressure. Accordingly, the patella bracingpad 15 can be said to more freely move with the flexion and extension ofthe knee.

To this end, counterarm, 19 includes an elastic portion 14, preferablyhaving greater elasticity than counterarm 19. The elastic portion isdisposed intermediate the anchor 16 and the pad 15. When the anchor 16is engaged with the fastener 12 and the knee is flexed, expansion of thesleeve 20 and its aperture 21 will permit the patella bracing pad todynamically float and align its position with respect to the patelladuring flexing of the knee. This dynamic repositioning of the pad 15 ispossible due to the anchor 16 and fastener 12 arrangement describedabove, in combination with the elastic portion 14. Fixing the anchor 16at a predetermined position close to the patella, at a distancepreferably in the range of about two inches, affords an additionaldegree of freedom in the lateral direction when the knee is flexed. Theanchor 16 placed close to the pad 15 reduces the rigidity of theposition maintaining counterarm 19 in the vicinity of the patella,thereby allowing displacement of the pad 15 when the brace is in use.The additional degree of freedom of movement afforded the pad 15 by thepositioning of the anchor 16 and fastener 12 allows the pad todynamically and effectively reposition itself throughout the entirerange of flexion and movement of the knee when the brace is in use. Tofacilitate dynamic positioning of the patella bracing pad 15, theelastic portion 14 of the counterarm 19 is preferably made of a materialhaving greater elasticity than the material of the counterarm, member19. The greater elasticity of the elastic portion 14 of the counterarmmember 19 assists in reducing the rigidity of the maintaining structureof the brace when the anchor 16 is engaged with the fastener 12. Theanchor 16 permits isolation of the elastic portion 14 of the counterarm,member 19 from the strap portion 31 of the assembly 30. Thus, when theknee is flexed, the tendency of the patella bracing pad 15 to be rigidlymaintained in position with respect to the patella is avoided by aresultant stretching of the elastic member 14. The patella bracing pad15 is thus permitted to float and dynamically follows movements of thepatella when the knee is flexed.

FIG. 2 shows further details of the strap assembly 30 of the dynamicpatella brace 10. As shown, the first and second arm member 17, 18 andthe counterarm member 19 are all operatively connected to one another atthe central strap portion 31. The patella bracing pad 15 is alsoattached the central strap portion 31 to which all arm members 17, 18,19 are attached. The patella bracing pad 15 is preferably attached tothe central strap portion 31 by a permanent adhesive. Alternatively, thepatella bracing pad 15 may be stitched or otherwise attached to thecentral strap portion 31. As further shown in FIG. 2, the anchor 16 ismade of a material which is fastenable to the fastening area 12 on thesleeve 20. Preferably, this material is made up of a Velcro® strip whichwould mate with an opposing Velcro® strip 12. Alternatively, the anchor16 could be a snap, button, or the like, so long as the anchor 16 wouldfunction to isolate the elastic portion 14 of the counterarm 19, and beproperly fastenable to the fastener 12 when the brace is in use asdescribed above.

In a preferred embodiment, the diameter of the elastic sleeve member 20and the elastic material and forces thereof are selected so as not tounduly constrict blood flow within the leg or knee of the user.

Preferably, a series of different size braces must be provided toaccommodate different users. Although a primary purpose of the sleeve 20and the aperture 21 therein is to permit a relatively unskilled user ofthe brace to achieve accurate alignment of the patella bracing padrelative to the patella, the elastic sleeve member 20 also inhibitssliding movement of the brace about the knee. However, it is thearrangement, wrapping and fastening of the arm 17, 18, counterarm 19members and the anchor 16 and fastening means 12 about the knee 16 whichprimarily cause the patella bracing pad 15 to be maintained in anautomatically dynamically repositionable manner laterally of the patellaand to cause resultant medially directed pressure thereto throughout thenormal range of flexion and movement of the knee by facilitating dynamicrepositioning of the patella bracing pad 15 with respect to the patellawhen the brace is in use.

It should also be noted that the patella bracing pad 15 is preferablyarcuately shaped, concave towards the aperture 21 which is adapted to beadjacent the patella when the patella is initially in its normalvertical track defined by the trochlea when the brace is first applied.The bracing pad 15 also preferably has a thickness of elevation to itand is preferably formed from a partially resilient padding materialadapted to permit the pad 15 to contour itself to the patella againstwhich it applies the medially directed force. It is also pointed outthat the bracing pad 15 will tend to dynamically confine the patella toits normal up-and-down movement in the vertical track defined by thetrochlea. In particular, during full flexion or bending of the knee, theupper and lower portions of the bracing pad 15 will bend with the kneeand will provide pressure surfaces to continuously provide medialpressure against the patella to prevent subluxation in the lateraldirection. As previously noted, however, providing an elastic portion14, isolated by the anchor 16, prevents the tendency of the patellabracing pad 15 to be rigidly maintained in a less effective positionwith respect to the patella when the knee is flexed and the sleeve 20and its aperture 21 are thereby expanded. This arrangement provides anadditional degree of freedom to the dynamic patella brace which furtherprovides continuous and effective medial pressure against the patellathrough all flexion and extension of the knee.

In another embodiment, the material used to make up the elastic portion14 of the counterarm 19 may be made up of the same material as thecounterarm 19, so long as the anchor is positioned such that itdecreases the rigidity of the counterarm 19 when it is engaged, and in amanner that isolates the elastic portion 14, thereby facilitatingautomatic dynamic repositioning of the patella bracing pad 15 withrespect to the patella when the brace is in use.

It may now be seen that the dynamic patella brace 10 of the presentinvention may be advantageously used to prevent patella instability inthe user during all normal degrees of knee flexion and extension. Unlikeprior devices, the combination of elastic sleeve 20, circumferentiallywrapped arms 17, 18, the circumferentially wrapped counterarm 19 and theisolated elastic portion 14 of the counterarm member 19, isolated by theanchor 16, cause the patella bracing pad 15 to be automaticallydynamically repositioned to maintain a more effective and properposition laterally of the patella during all normal degrees of kneeflexion and motion and to apply medially directed pressure to thepatella of the user to prevent subluxation.

In another embodiment of the present invention, as shown in FIGS. 4 and5, the counterarm member 19 (shown in FIGS. 1 and 2) is removed. In thisembodiment, the dynamic patella brace 10 includes an elastomeric sleeve20 having an aperture 21 in which the knee is positioned during use, anda strap assembly 30 comprising a central strap portion 31, elastic armmembers 17 and 18 extending therefrom, patella bracing pad 15 and anchor16. The sleeve 20, including the aperture 21 and a fastener 12, issubstantially identical to that described above with respect to FIGS.1-3. The dynamic patella brace 10, according to this alternateembodiment of the present invention, is positioned on the knee betweenthe upper portion and lower portion of the leg of the user (not shown).The elastic arm members 17, 18 of the dynamic patella brace 10 areadapted to be wound about the knee of the user when the brace is in use.Each of the elastic arm members 17, 18 extends from the strap assembly30', on which is disposed the patella bracing pad 15 and arranged sothat, when wrapped about the user's knee when the brace is in use, thebracing pad 15 will thereby cause a resultant force to be appliedmedially to the user's patella. Fastening and holding of the arm members17, 18 in position is accomplished in the manner described above withrespect to FIGS. 1 and 2.

In the alternate embodiment shown in FIGS. 4 and 5, instead of having acounterarm 19 extending from the central strap portion 31, the centralstrap portion 31 is elongated and the anchor 16 is disposed directlythereon.

The central strap portion 31 also includes an elastic strip portion 14disposed adjacent to the anchor 16 and in between the patella bracingpad 15 and the anchor 16. The anchor is adapted to be fastened to thefastener 12, which is positioned on the sleeve 20 as described above.

By fixing the anchor 16 to the fastener 12 and having the elastic stripportion 14 disposed in the central strap portion 31 between the patellabracing pad 15 and the anchor 16, the patella bracing pad 15 ispermitted to float with the movement of the knee to provide moreefficient and stable support to the patella during the entire range offlexion and movement of the knee when the brace is in use, as describedabove.

To this end, when the anchor 16 is engaged with the fastener 12 and theknee is flexed, expansion of the sleeve 20 and its aperture 21 willpermit the patella bracing pad 15 to dynamically float and align itsposition with respect to the patella during flexion of the knee byvirtue of the above-described construction of the central strap portion31 including the anchor 16 and the elastic strip portion 14 positionedadjacent the anchor 16.

As described above, fixing the position of the anchor 16 at apredetermined position close to the patella, preferably a distance inthe range of about two inches from the patella, affords an additionaldegree of freedom in the. lateral direction when the knee is flexed. Theanchor 16 placed close to the pad 15 reduces the rigidity of thelocation of the patella bracing pad 15 in the vicinity of the patella,thereby allowing lateral and medial displacement of the pad 15 when thebrace is in use, thus providing closer tracking and control of thepatella. The operation of this embodiment of the dynamic patella brace10 of the present invention is substantially the same as that describedabove, with the requirement of having a counterarm member beingeliminated.

FIG. 5 shows further details of the strap assembly is 30'. In thisembodiment, the strap assembly 30' comprises a central strap portion 31,elastic arm members 17, 18 extending therefrom, patella bracing pad 15,anchor 16 and elastic strip portion 14 disposed between the patellabracing pad 15 and the anchor 16. Similarly to the strap assembly shownin FIG. 2, the patella bracing pad 15 is preferably attached to thecentral strap portion 31 by a permanent adhesive. Alternatively, thepatella bracing pad 15 may be stitched or otherwise attached to thecentral strap portion 31. The anchor 16 and fastener 12 arrangement issimilar to that described above.

It should also be understood that the anchor 16 and fastener 12arrangement of the patella brace embodiments described herein may bereplaced with an arrangement whereby the anchor 16 is permanentlysecured to the sleeve 20, such as, for example, by stitching 27 or,alternatively, by a permanent adhesive. Constructing the brace 10 inthis manner will not affect the performance of the brace and will resultin having a single integrated unit that may be less cumbersome whenbeing put on by the user.

The brace 10 of the invention may also be adapted to be used on eitherknee of the user. This can be accomplished by providing a fastener in apredetermined location on the sleeve 20 on both sides of the aperture 21similar to the fastener 12 shown in FIG. 3. By locating a secondfastener an equal distance from and opposite of the aperture 21 as thefirst fastener 12, the sleeve 20 can be used on either the left or rightleg of the user since the strap assembly 30 is independent of the sleeve20.

It is also believed that dynamic patella braces, according to thepresent invention, are useful for treating patella instabilities bypreventing further stretching of the ligaments. With repeatedsubluxation, the medial patellal femoral and medial patellar tibialligaments of the patellae (retinaculum) becomes stretched and thelateral ligament (retinaculum) tightens (shortens), tending to morereadily permit further subluxation occurrences. If the patella brace,according to the present invention, is utilized, however, the patellawill be confined to its normal up-and-down, vertical track defined bythe trochlea, and, therefore, prevent the development of, or stretch, analready tight lateral retinaculum. Thus, the need for corrective surgerymay be avoided. It is also believed that the patella stabilizing bracemay be useful in certain forms of isolated patellofemoral chondromalaciaby changing opposing contact or pressure points which-are frequentlypainful. Accordingly, it has been seen that the dynamic patella brace,accordingly to the present invention, accomplishes the above-describedobjectives, as well as other objects which will be apparent to thoseskilled in the art.

While this invention has been described in conjunction with specificembodiments thereof, it is evident that many alternatives, modificationsand variations will be apparent to those skilled in the art.Accordingly, the preferred embodiments of the invention, as set forthherein, are intended to be illustrative, not limiting. Various changesmay be made without departing from the true spirit and full scope of theinvention, as defined in the following claims.

What is claimed is:
 1. In a dynamic patella brace having a kneeenveloping member with an aperture adapted to expose the knee, and ameans for applying medial pressure to the patella, the improvementcomprising mounting means for substantially freely floatingly mountingsaid means for applying medial pressure on said knee enveloping memberlaterally of said aperture so that said means for applying medialpressure moves relative to said knee enveloping member in verticaldirections and automatically tracks vertical and horizontal movements ofsaid patella throughout the functional physiological range of flexionand movement of the knee while applying said medial pressure to saidpatella, said mounting means accommodating horizontal excursion therebyallowing more controlled horizontal medial pressure and trackingvertical movements of said patella.
 2. The dynamic patella brace definedin claim 1 wherein said means for applying medial pressure includes apatella pad.
 3. The dynamic patella brace defined in claim 2 whereinsaid means for floatingly mounting said patella bracing pad on said kneeenveloping member includes a patella bracing strap and anchor means,first and second arm members extending from said strap, first ends ofsaid :first and second arm members being adapted to be wrapped about aknee of a user to apply a dynamic resultant force in the medialdirection to the patella via the patella bracing pad.
 4. The dynamicpatella brace defined in claim 1 wherein said knee enveloping member isan elastomeric sleeve.
 5. A method dynamically stabilizing the patellaof a human knee for diagnosis and treatment of pathological patellaconditions including patellar instabilities during flexion movementcomprising:a) enveloping said human knee with a knee enveloping memberhaving an aperture adapted to minimize compressive pressure on thepatella, b) applying medial pressure to the patella with a freelyfloating patella bracing pad along a path automatically trackingvertical movement of said patella throughout the functionalphysiological range of flexion and extension of said knee.
 6. In adynamic knee brace having a device for applying medial pressure to thepatella during flexion extensions of the knee, the improvementscomprising, first and second knee enveloping members,said first kneeenveloping member having an inside and an outside and an apertureadapted to be positioned over the patella and at least one anchor memberlocated laterally of said aperture on said outside a fixed distance fromsaid aperture, said second knee enveloping member having a coactinganchor member secured thereto so that said second knee enveloping membercan be horizontally adjusted relative to said first knee envelopingmember, said second knee enveloping member having a patella engagingmember and an elastic portion located between said patella engagingmember and said coacting anchor member, whereby said patella engagingmember substantially freely tracks vertical and horizontal movement ofsaid patella during flexion movements of said knee.